ExxonMobil

About: ExxonMobil is a company organization based out in Irving, Texas, United States. It is known for research contribution in the topics: Catalysis & Polymerization. The organization has 16969 authors who have published 23758 publications receiving 535713 citations. The organization is also known as: Exxon Mobil Corporation & Exxon Mobil Corp..

Experimental Study of Dynamic Permeability in Porous Media

Abstract: We report experimental measurements of ac permeability made on a variety of fused glass beads and crushed glass in a frequency range of 0.1 Hz to 1 kHz. We observe a rollover in $\ensuremath{\kappa}(\ensuremath{\omega})$ from a viscous flow regime to an inertial one, and determine the values of the transport coefficients in both the high-frequency limit and the low-frequency limit. A good agreement is found with the scaling theory $\frac{\ensuremath{\kappa}}{{\ensuremath{\kappa}}_{0}}=f(\frac{\ensuremath{\omega}}{{\ensuremath{\omega}}_{c}})$ with only two independent parameters.

Dynamic permeability in porous media.

Abstract: We calculate from first principles the frequency-dependent permeability $\ensuremath{\kappa}(\ensuremath{\omega})$ in porous media for a variety of microstructures. It is found that when $\ensuremath{\kappa}(\ensuremath{\omega})$ is scaled by its static value ${\ensuremath{\kappa}}_{0}$ and the frequency by a characteristic ${\ensuremath{\omega}}_{c}$ particular to the sample, the resulting function exhibits excellent universal behavior independent of microstructure. We advance arguments that delineate the physical reason for the scaling behavior as well as the condition for its validity. Our predictions are supported by observed correlations in sedimentary rocks and experimental $\ensuremath{\kappa}(\ensuremath{\omega})$ measurements.

Workgroup Report: Review of Fish Bioaccumulation Databases Used to Identify Persistent, Bioaccumulative, Toxic Substances

Abstract: Chemical management programs strive to protect human health and the environment by accurately identifying persistent, bioaccumulative, toxic substances and restricting their use in commerce. The advance of these programs is challenged by the reality that few empirical data are available for the tens of thousands of commercial substances that require evaluation. Therefore, most preliminary assessments rely on model predictions and data extrapolation. In November 2005, a workshop was held for experts from governments, industry, and academia to examine the availability and quality of in vivo fish bioconcentration and bioaccumulation data, and to propose steps to improve its prediction. The workshop focused on fish data because regulatory assessments predominantly focus on the bioconcentration of substances from water into fish, as measured using in vivo tests or predicted using computer models. In this article we review of the quantity, features, and public availability of bioconcentration, bioaccumulation, and biota-sediment accumulation data. The workshop revealed that there is significant overlap in the data contained within the various fish bioaccumulation data sources reviewed, and further, that no database contained all of the available fish bioaccumulation data. We believe that a majority of the available bioaccumulation data have been used in the development and testing of quantitative structure-activity relationships and computer models currently in use. Workshop recommendations included the publication of guidance on bioconcentration study quality, the combination of data from various sources to permit better access for modelers and assessors, and the review of chemical domains of existing models to identify areas for expansion.

Vessel mooring system

Abstract: The disclosure describes apparatus for mooring a vessel 10 in unprotected waters. The vessel 10 contains a recess 34 in its hull adapted for receiving a buoyant mooring element 18. The mooring element 18 is attached to the ocean floor 12 by a plurality of mooring lines 20. Means are provided for releasably securing the mooring element 18 within the recess 34. The buoyancy of the mooring element is established such that on release from the vessel 10 it sinks to a predetermined depth a spaced distance above the ocean floor. The apparatus of the present invention is especially well suited for mooring a hydrocarbon storage tanker proximate the terminus of a production riser in waters subject to ice floes.

Method for borehole measurement of formation properties

Abstract: The present invention is a method for estimating formation properties (4), by analyzing acoustic waves (20) that are emitted from and received by a bottom hole assembly (14).